Enhanced Lifetime Of Excitons In Nonepitaxial Au/cds Core/shell Nanocrystals

The ability of metal nanoparticles to capture light through plasmon excitations offers an opportunity for enhancing the optical absorption of plasmon-coupled semiconductor materials via energy transfer. This process, however, requires that the semiconductor component is electrically insulated to prevent a backward charge flow into metal and interfacial states, which causes a premature dissociation of excitons. Here we demonstrate that such an energy exchange can be achieved on the nanoscale by using nonepitaxial Au/CdS core/shell nanocomposites. These materials are fabricated via a multistep cation exchange reaction, which decouples metal and semiconductor phases leading to fewer interfacial defects. Ultrafast transient absorption measurements confirm that the lifetime of excitons in the CdS shell (tau approximate to 300 ps) is much longer than lifetimes of excitons in conventional, reduction-grown Au/CdS heteronanostructures. As a result, the energy of metal nanoparticles can be efficiently utilized by the semiconductor component without undergoing significant nonradiative energy losses, an important property for catalytic or photovoltaic applications. The reduced rate of exciton dissociation in the CdS domain of Au/CdS nanocomposites was attributed to the nonepitaxial nature of Au/CdS interfaces associated with low defect density and a high potential barrier of the interstitial phase

Globally, songs and instrumental melodies are slower and higher and use more stable pitches than speech: A Registered Report

Both music and language are found in all known human societies, yet no studies have compared similarities and differences between song, speech, and instrumental music on a global scale. In this Registered Report, we analyzed two global datasets: (i) 300 annotated audio recordings representing matched sets of traditional songs, recited lyrics, conversational speech, and instrumental melodies from our 75 coauthors speaking 55 languages; and (ii) 418 previously published adult-directed song and speech recordings from 209 individuals speaking 16 languages. Of our six preregistered predictions, five were strongly supported: Relative to speech, songs use (i) higher pitch, (ii) slower temporal rate, and (iii) more stable pitches, while both songs and speech used similar (iv) pitch interval size and (v) timbral brightness. Exploratory analyses suggest that features vary along a “musi-linguistic” continuum when including instrumental melodies and recited lyrics. Our study provides strong empirical evidence of cross-cultural regularities in music and speech

Globally, songs and instrumental melodies are slower, higher, and use more stable pitches than speech: a registered report

Both music and language are found in all known human societies, yet no studies have compared similarities and differences between song, speech, and instrumental music on a global scale. In this Registered Report, we analyzed two global datasets: (i) 300 annotated audio recordings representing matched sets of traditional songs, recited lyrics, conversational speech, and instrumental melodies from our 75 coauthors speaking 55 languages; and (ii) 418 previously published adult-directed song and speech recordings from 209 individuals speaking 16 languages. Of our six preregistered predictions, five were strongly supported: Relative to speech, songs use (i) higher pitch, (ii) slower temporal rate, and (iii) more stable pitches, while both songs and speech used similar (iv) pitch interval size and (v) timbral brightness. Exploratory analyses suggest that features vary along a “musi-linguistic” continuum when including instrumental melodies and recited lyrics. Our study provides strong empirical evidence of cross-cultural regularities in music and speech

Economic responsiveness and the political conditioning of the electoral cycle

Understanding the drivers of party issue emphasis and the specific role of public opinion is important to shed light on the mechanisms of contemporary party competition and to assess the quality of representation in liberal democracies. Previous research has produced conflicting results between issue ownership and issue dialogue perspectives and has ignored the role of time in party communication strategy. We present a theory focused on the economy in which proximity to election day increases the incumbent’s cost of not responding to opponent attacks and subsequently decreases the incumbent’s attention to public opinion. We validate the main empirical implications of the model via content analysis of party discourse in Spanish parliamentary speeches (1996–2011) and time series analyses. Our results have pessimistic implications for an ideal conception of bottom-up representation. As electoral accountability pressures increase over the electoral cycle, endogenous party competition overshadows public opinion as a driver of representatives’ agenda

Trayectorias docentes e investigadoras en la universidad. 24 historias de vida profesional. Los efectos de los cambios en el trabajo y la vida profesional de los docentes universitarios

[spa] Este texto forma parte de un proyecto de investigación Los efectos de los cambios sociales en el trabajo y la vida profesional de los docentes universitarios, parcialmente financiado por el Ministerio de Ciencia e Innovación (SEJ2006-01876), en el que nos planteamos explorar los cambios los ámbitos de la legislación, la organización institucional, la investigación, la gestión y la docencia en los últimos treinta años. El principal objetivo del estudio era profundizar en nuestra comprensión sobre el impacto del cambio económico, social, cultural, tecnológico y laboral que están experimentando las universidades españolas en la vida y la identidad profesional del personal docente e investigador, teniendo en cuenta el contexto nacional y europeo. Esta publicación recoge la 24 historias de vida profesional realizas con o sobre otros tantos docentes universitarios. Sus relatos analizados y contextualizados, significan una contribución significativa al conocimiento basado en la investigación sobre el saber profesional y la experiencia laboral en las universidades españolas, y en consecuencia, a nuestra comprensión sobre cómo los académicos se están enfrentando con los cambios actuales.[cat] Aquest text forma part d'un projecte d'investigació "Els efectes dels canvis socials en el treball i la vida professional dels docents universitaris", parcialment finançat per el Ministeri de Ciència i Innovació (SEJ2006-01876), on ens plantejavem explorar els canvis en els àmbits de legislació, l'organització institucional, la investigació, la gestió i la docència en els darrers trenta anys. El principal objectiu de l'estudi era aprofundir en la comprensió de l'impacte del canvi enconòmic, social, cultural, tecnològic i laboral que están experimentant les universitats espanyoles en la vida i la identitat professional del personal docent i investigador, tenint en compte el context nacional i europeu. Aquesta publicació recull 24 històries de vida professionals realitzades amb o sobre els docents universitaris. Els seus relats analitzats i contextualitzats, signifiquen una contribució significativa al coneixement basat en la investigació sobre el saber professional i l'experiència laboral a les universitats espanyoles, i en conseqüència, a la nostra comprensió sobre com els acadèmics s'estan enfrontant amb els canvis actuals.[eng] This text is part of a research project “The effects of social change at work and professional life of academics”, partly funded by the Ministry of Science and Innovation (SEJ2006-01876), in which we explored change in legislation, institutional organization, research, management and education in the last thirty years. The main objective of the study was to deepen our understanding of the impact of economic, social, cultural, technologicaland labour change undergoing in Spanish universities in the professional life and identity of teachers and researchers, taking into account the national and European contexts. This publication contains the 24 professional life histories developed about or with many other university teachers. Their analysed and contextualized narrativesare a significant contribution to research-based knowledge on professional knowledge and experience in Spanishuniversities, and therefore for our understanding of how scholars are facing and coping with current change.Ministerio de Educación y Ciencia. SEJ2006-0187